As a result of remarkable technical progress in recent years, tape recorders, video decks or other cassette type magnetic recording apparatuses, in general, are configured to activate a cassette loading driving motor when a cassette is inserted by a predetermined stroke, so as to automatically conduct a further movement of the cassette (cassette loading) to a play position, using a motor driving power.
In such a cassette loading mechanism, if a cassette is manually inserted in an inclined configuration, and if the inclined cassette i automatically transported further, the cassette hits opposed walls or other members in the recording apparatus, and often injures the apparatus and itself.
In this connection, some prior art cassette type magnetic recording apparatus includes a cassette insertion detecting mechanism for detecting whether an inserted cassette takes a proper angular position with respect to a cassette holder or not, so that a subsequent loading operation is taken only when the cassette takes the proper position.
The Assignee of this application already proposed a cassette insertion detecting mechanism in which a cassette holder is divided into right and left halves which can be driven independently, and a detection switch provided on a side wall of the apparatus detects the position of the cassette holder (Japanese patent application No. 166054/1986).
As compared to an old arrangement in which a detection switch is supported on a cassette holder which is a movable member, the aforegoing Applicant's improvement supports the detection switch on a side wall which is a fixed member in the apparatus, and this permits omission of lead wires or flexible board for wiring. Therefore, the Applicant's prior art mechanism is excellent in durability and contributes to a dimensional reduction of the apparatus. However, it also involves the following problems.
When the positions of both cassette holder halves are detected upon insertion of a cassette, the cassette holder halves start their motions with the energy of a driving motor. After this, if the cassette is removed from the apparatus before moved to its loading position, the mechanism undertakes a cassette loading operation in absence of the cassette, because the apparatus does not include any means which detects such an interrupting removal of the cassette to stop a subsequent cassette loading operation.
This problem will be overcome by using an insertion detecting member configured to slide while engaging a cassette and also movable with respect to the cassette holders. However, this arrangement requires a vertical overlapping configuration of the bottom plates of the cassette holders and the insertion detecting member, and hence unables vertical dimensional reduction of the apparatus.